Solution :
Given that,
Point estimate = sample mean =
= $12.16
Population standard deviation =
= $1.87
Sample size = n =44
At 99% confidence level the z is ,
= 1 - 99% = 1 - 0.99 = 0.01
/ 2 = 0.01 / 2 = 0.005
Z_{/2} = Z_{0.005} = 2.576
Margin of error = E = Z_{/2}* ( /n)
= 2.576 * ( 1.87/ 44)
= 0.7
At 99% confidence interval estimate of the population mean is,
- E < < + E
12.16 - 0.7 < <12.16 + 0.7
11.5< < 13.2
(lower limit $11.5 , upper limit$13.2)
part b: what is the margin of error for this interval? Banking fees have received much...
Also, need Margin of error. Banking fees have received much attention during the recent economic recession as banks look for ways to recover from the crisis. A sample of 44 customers paid an average fee of $11.53 per month on their interest-bearing checking accounts. Assume the population standard deviation is $1.61. Complete parts a and b below. a. Construct a 95% confidence interval to estimate the average fee for the population. The 95% confidence interval has a lower limit of...
Banking fees have received much attention during the recent economic recession as banks look for ways to recover from the crisis. A sample of 32 customers paid an average fee of $12.11 per month on their interest-bearing checking accounts. Assume the population standard deviation is $1.65 Complete parts a and b below. a. Construct a 90% confidence interval to estimate the average fee for the population.The 90% confidence interval has a lower limit of blank and an upper limit of....
part b: what is the margin of error for this sample? part c: is there any evidence that this proportion has changed since 2008 based on this sample? According to a health organization in a certain country, 21.8% of the population smoked in 2008. In 2014, a random sample of 750 citizens of this country was selected, 141 of whom smoked. Complete parts a through c below. Nam a. Construct a 99% confidence interval to estimate the actual proportion of...
part b: what assumptions need to be about this population? Arandom sample of 15 college men's basketball games during the last season had an average attendance of 5,085 with a sample standard deviation of 1,781. Complete parts a and below. a. Construct a 90% confidence interval to estimate the average attendance of a college men's basketball game during the last season The 99% confidence interval to estimate the average attendance of a college men's basketball game during the last season...
part b. What assumptions need to be made to construct this interval? Golf cart attendants at a local country Club often receive tips from golfers they assist with golf clubs. To help recruit new employees, the country club would like to determine the average tips per day an attendant eams. A sample of 14 attendants averaged $40.74 per day in tips. Assume the population standard deviation for daily tips is $8.72. Complete parts a and b below. a. Construct a...
Case: Enron: Questionable Accounting Leads to CollapseIntroductionOnce upon a time, there was a gleaming office tower in Houston, Texas. In front of that gleaming tower was a giant “E,” slowly revolving, flashing in the hot Texas sun. But in 2001, the Enron Corporation, which once ranked among the top Fortune 500 companies, would collapse under a mountain of debt that had been concealed through a complex scheme of off-balance-sheet partnerships. Forced to declare bankruptcy, the energy firm laid off 4,000...